Closes stdin after starting a new process for a test.

tools/testing/dart/test_runner.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * Classes and methods for executing tests.
  *
  * This module includes:
  * - Managing parallel execution of tests, including timeout checks.
  * - Evaluating the output of each test as pass/fail/crash/timeout.
@@ skipping 944 matching lines @@
     command.outputIsUpToDate.then((bool isUpToDate) {
       if (isUpToDate) {
         compilationSkipped = true;
         _commandComplete(0);
       } else {
         var processOptions = _createProcessOptions();
         Future processFuture = io.Process.start(command.executable,
                                                 command.arguments,
                                                 processOptions);
         processFuture.then((io.Process process) {
+          // Close stdin so that tests that try to block on input will fail.
+          process.stdin.close();
           void timeoutHandler() {
             timedOut = true;
             if (process != null) {
               process.kill();
             }
           }
           process.exitCode.then(_commandComplete);
           _drainStream(process.stdout, stdout);
           _drainStream(process.stderr, stderr);
           timeoutTimer = new Timer(new Duration(seconds: testCase.timeout),
@@ skipping 741 matching lines @@
     }
   }
 
   void eventAllTestsDone() {
     for (var listener in _eventListener) {
       listener.allDone();
     }
   }
 }